Erm, ok. I'll look for a good shielded cable..
On Mon, Oct 28, 2013 at 10:42 PM, Paulo Ferreira <[email protected]> wrote: > You issue may be there (or not). > > To really really know, you can use some wide bandwidth digital > oscilloscopes to see how the USB signals are behaving. > Or try to use a good shielded USB cable. > > Guess what is the cheapest option, try it, and after that please tell us > what did you find. > > Best regards > Paulo Ferreira > > > > > > > > On 28/10/2013, at 14:22, Bai Shi <[email protected]> wrote: > > > Erm.. very good question. It indeed is the same external power supply > connected to the Beagle Board. Or I would say all the power come from the > same ATX power supply though it might (tiny little chance) be in different > rails. > > > > Frankly speaking the line was rather short (less than 5cm) so I didn't > bother to do shielding at all. The D+ and D- is using Cat5 ethernet cable. > > > > Does it make any significance? > > > > Regards, > > Bai Shi > > > > > > On Mon, Oct 28, 2013 at 9:56 PM, Paulo Ferreira <[email protected]> wrote: > > > > On 28/10/2013, at 13:27, Bai Shi <[email protected]> wrote: > > > > > My usb device draws power from external power supply, only D+ and D- > is connected to BBB. It works 90% of time but when I mess around too much > (on/off too frequently maybe, not confirmed), it will reset the USB of BBB > and then it will behave very strangely. Every access to /sys/bus/usb take > more than 15 seconds and timeout eventually. > > > > > > Hope my experience gives some hint... > > > > Is the same external power supply connected to the Beagle Board? > > > > So, the ground shield of the USB cable is connect only on one side (the > device) or is it completely "floating"? > > > > Best regards > > > > Paulo Ferreira > > > > -- > > For more options, visit http://beagleboard.org/discuss > > --- > > You received this message because you are subscribed to a topic in the > Google Groups "BeagleBoard" group. > > To unsubscribe from this topic, visit > https://groups.google.com/d/topic/beagleboard/nuyyVDhU6bw/unsubscribe. > > To unsubscribe from this group and all its topics, send an email to > [email protected]. > > For more options, visit https://groups.google.com/groups/opt_out. > > > > > > -- > > For more options, visit http://beagleboard.org/discuss > > --- > > You received this message because you are subscribed to the Google > Groups "BeagleBoard" group. > > To unsubscribe from this group and stop receiving emails from it, send > an email to [email protected]. > > For more options, visit https://groups.google.com/groups/opt_out. > > -- > For more options, visit http://beagleboard.org/discuss > --- > You received this message because you are subscribed to a topic in the > Google Groups "BeagleBoard" group. > To unsubscribe from this topic, visit > https://groups.google.com/d/topic/beagleboard/nuyyVDhU6bw/unsubscribe. > To unsubscribe from this group and all its topics, send an email to > [email protected]. > For more options, visit https://groups.google.com/groups/opt_out. > -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/groups/opt_out.
